Ch. 11 Flashcards
1
Q
- The control loop is made up of four basic functional blocks:
1) Process
2) Process Variable
3) Measurement
4) Automatic controller
5) The final control element
a. 1, 3, 4, 5
b. 3, 4
c. 1, 2, 3
d. 1, 2, 3, 4, 5
A
a. 1, 3, 4, 5
2
Q
- For purposes of control theory, a process can be defined as an action in which material and/or ________ is modified to a different form.
a. fluids
b. energy
c. gas
d. oil
A
b. energy
3
Q
- Process parameters such as temperature, pressure, and flow require continuous measurements in real time. If review of the measurements is desired, provision must be made to capture the parameters with respect to time.
a. True
b. False
A
a. True
3
Q
- Flow rate is often measured with a _________________.
a. pedometer
b. ultrasonic meter
c. orifice plate
d. velocity meter
A
c. orifice plate
4
Q
- List the four types of final actuators:
1) Conveyor belt
2) Flapper valve
3) Globe valve
4) A louver
5) Motor’s variable speed drive
6) A compressor’s inlet guide vanes
a. 1, 2, 3, 4, 5, 6
b. 1, 6
c. 4, 5, 6
d. 1, 4, 5, 6
A
d. 1, 4, 5, 6
5
Q
- Pneumatic systems can operate on:
1) Compressed air
2) Hydraulic fluid
3) Nitrogen
4) Water
5) Methane
a. 1, 2, 3, 4, 5
b. 1, 3, 5
c. 1, 5
d. 1, 2, 5
A
b. 1, 3, 5
5
Q
- Transmitters convert a process physical quantity such as level, pressure, flow, or temperature into a representative pneumatic analog signal, usually ________.
a. 0 - 25 kpa
b. 20 - 100 kPa
c. 4 - 20 mA
d. 1 - 100 %
A
b. 20 - 100 kPa
6
Q
- Control valves are responsible for providing process changes by manipulating fluid flow in a pipeline. They are called a “Primary Control Element” (PCE), as they are the final devices that the controller uses to affect corrective action to the process.
a. True
b. False
A
b. False
7
Q
- List the three main elements of an Analog Instrumentation Loop.
1) Process setpoint
2) Transmitter
3) Controller
4) Instrument air
5) Final control element
a. 1, 2, 3, 4, 5
b. 2, 3, 5
c. 1, 3, 4,
d. 1, 2, 3, 4, 5
A
b. 2, 3, 5
7
Q
- Pneumatic switches are available for:
1) Level
2) Pressure
3) Viscosity
4) Temperature
5) Density
6) Flow
a. 1
b. 1, 2, 3
c. 1, 4, 5, 6
d. 1, 2, 4, 6
A
d. 1, 2, 4, 6
8
Q
- __________ are used to convert physical quantities of flow, level, temperature, pressure, and weight into electrical signals that represent those quantities as accurately as possible.
a. Controllers
b. Control valves
c. Transmitters
d. Level switches
A
c. Transmitters
9
Q
- The controller uses an operational amplifier to perform a mathematical summation, in order to compare the input signal (process variable) with a setpoint that is established by operations personnel. If the process is not at the set value, the mathematical functions present in the controller will produce an output signal that will correct the process.
a. True
b. False
A
a. True
9
Q
- Square root extractors are used to convert squared signals from _______ flowmeters to ______ flow signals.
a. digital, analog
b. differential, linear
c. normal, normal
d. steam, boiler feedwater
A
b. differential, linear
10
Q
- The main devices used as final control elements are:
1) Control valves
2) Variable speed motor drives (VSDs)
3) Steam flow
4) Speed governors
5) Level switches
6) Damper positioners
a. 1, 6
b. 4, 5, 6
c. 1, 2, 6
d. 1, 2, 4, 6
A
d. 1, 2, 4, 6
10
Q
- A typical controller station allows the operator to:
1) View and change the setpoint
2) View feed forward settings
3) View the process variable
4) Switch from Auto to manual
5) View process history
a. 1, 2, 3, 4
b. 1, 2, 3, 4, 5
c. 1, 3, 5
d. 1, 2
A
c. 1, 3, 5